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A simple X11 tea timer
wrapping the snippet in $( )& puts the whole thing in the background so you don't tie up your login session.

Find top 10 largest files in /var directory (subdirectories and hidden files included )
Same as above, but modified to show human readable output

Open Port Check
also could specify port number: lsof -ni TCP:80

Using numsum to sum a column of numbers.
numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line. Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
This version eliminates the grep before the awk, which is always good. It works for GNU core utils and ensures that the date output of ls matches the format in the pattern match, regardless of locale, etc. On BSD-based systems, you can easily eliminate both the grep and the awk: find . -maxdepth 1 -Btime -$(date +%kh%lm) -type f

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

for all who don't have the watch command
#Usage: watch timeinsecond "command"

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Archive all folders in a directory into their own tar.bz2 file
Remove the "echo" to actually archive. Many similar commands are found on commandlinefu but I end up needing this very specific one from time to time. To extract any of them, use the standard tar.bz2 extract command: $tar xvjf folder1.tar.bz2

RTFM function
Sometimes you don't have man pages only '-h' or '--help'.


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